Certain individuals have problems with short term memory recall and these problems generally increase with aging. It is very frustrating for these individuals to walk from one room to another for a purpose which has been forgotten by the time they reach the next room, for example.
One may carry a note pad or slate and write oneself messages. Alternatively, one may carry a small tape recorder and tape and playback messages. This requires manipulation of a number of different buttons in a correct sequence that may be awkward and time consuming or impossible for users with certain infirmities and involves a large, fragile and cumbersome device with many moving parts. The same patients with memory deficit may also have other mental and dexterity problems so that conventional recorders are quite beyond their abilities while their need for such a device is greatest.